BTW not sure if this was said but the DLC is gonna be given free to active players on Sept 6th so if you want to play DCUO get it now for PS# or PC and get to playing so on Sept 6th you can get the GL dlc 8)

From what I understand, it is a reboot, but it is starting 5 years into the reboot. A lot of the major events that happened in the old DCU also happened here (including the recent GL stories Blackest Night and War of the Green Lanterns). Some books are telling back story before jumping back up to now in the timeline, some are continuing right where they left off. Depends on the story. GL seems to be sticking to it's continuity more than some of the others, but the reboot is happening. It's just a matter of time to see what else is new.

This is not an alternate universe. A large portion of the books included in the reboot have been restarted and are telling more of an origin story. Green Lantern and Batman, though, are continuing with the same continuity but are being renumbered more so for a good jumping on point. These preview pages actually give a pretty good summation of what has happened with Sinestro in the past Green Lantern stories. So no, this isn't a complete reboot of Green Lantern and it's also not an alternate universe.

I'm a HUGE Green Lantern fans so I just thought I'd clear that up for everyone. :)

I believe it is a complete reboot; but with the Marvel AND DC Universe they have multiple universes. So I would not be surprise if you see a "CLASSIC" DC Universe comic line or story arc from time to time. I am not sure if "CLASSIC" is the correct word for DC because of the Silverage and golden age stuff. Sometimes the DC Universe has a worse time line than a Doctor Who series.

Is this a complete reboot of the DC Comics line or is just another alternative universe arc that eventually become null and void by yet another "Infinite Crisis" like event that will merge all the universes again?